Overhead lines electrical_hazards

AVOIDANCE OFELECTRICAL HAZARDS

WHEN WORKING NEAR OVERHEADELECTRIC LINES

ESB Code 9803203

overhead 23/11/04 2:28 PM

AVOIDANCE OF ELECTRICAL HAZARDS

WHEN WORKING NEAR OVERHEAD ELECTRIC LINES

Issued by: ESB NetworksDocument Reference: DTIS 191203-BOIStores Code: 9803203Issue Date: January 2004Review Cycle: 3Version: Revision 2

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Additional copies available from your local ESB Networks Area office

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Contents

Introduction 5

Statutory Regulations 5

Consultation 6

Switchout of Overhead Lines 7

Diversion of Overhead Lines 7

Working in Proximity of Overhead Lines 8

Sites where there will be no work or passage of plant 8under a Live Overhead Line (all work outside the ‘at risk zone’)

Sites where plant will pass under a live Overhead Line 10

Sites where work will be done within the ‘at risk zone’of an Overhead Line 11

Maintenance of barriers and warning notices 11

Special Precautions 11

Communicating the Safety Message 13

Emergency Contact Numbers 18

Acknowledgement of receipt of booklet 19

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WORKING NEAR OVERHEAD LINES

1. Introduction

People are killed and injured each year by accidental contact with overhead

electrical lines. Most of these accidents occur when cranes, excavators, tipper

trucks, crane mounted lorries, mobile extendable machinery, scaffolding,

ladders, farm machinery, concrete delivery trucks etc. come close to or touch

live overhead lines. Such accidents are caused by failure to take all practicable

precautions to prevent accidental contact with these lines. Recommended

methods and procedures are set out in this booklet which, if adopted, will

provide a positive approach to the elimination of these tragedies.

NOTE: GUARD AGAINST WORKING CLOSE TO LIVE OVERHEAD LINES.

IF AT ALL POSSIBLE KEEP MACHINERY WELL AWAY (OUTSIDE THEIR

REACH). PLAN THE WORK IN ADVANCE AND STAY SAFE.

IT IS YOUR RESPONSIBILITY TO ENSURE THAT ANY MACHINERY OR

EQUIPMENT (E.G. LADDERS, CRANES, SCAFFOLDING ETC.) SET UP

OUTSIDE THE ‘AT RISK ZONE’ (SEE SECTION 7) IS STABLE AND THAT

PRECAUTIONS ARE PUT IN PLACE TO PREVENT THEM FROM FALLING

INTO THE ‘AT RISK ZONE’.

2. Statutory Regulations

As with all work locations, there is an obligation under the Safety Health and

Welfare at Work Act 1989 to provide a safe place of work for all employees. It

is the duty of the employer when employees are working near overhead lines to

ensure that they are aware of the hazard. The erection of barriers, bunting and

goal posts as set out in chapters 6, 7, 8 and 9 of this booklet will alert

employees and the general public to the hazard and act as a warning to keep

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their distance.

The General Application Regulations S.I. 44 of 1993 state in regulation 52 that

overhead lines should be protected with suitable guards and barriers so as to

prevent dangerous contact with a person, article, substance or any conducting

material.

The nine Principles of Prevention which are also contained in the 1993 General

Application Regulations S.I.44, contain requirements on the avoidance,

evaluation and elimination of risk and the adaptation of the workplace to reduce

the risk. This imposes duties on the contractor to protect his/her employees

from the dangers associated with working near overhead lines.

Under the Construction Regulations S.I. No. 481 of 2001, the Project

Supervisor (Construction Stage) must specify the control measures for dealing

with the particular risks referred to in the preliminary safety and health plan,

which may also include other significant risks associated with the project.

Working near high voltage power lines is one of the listed hazards and must be

risk assessed and the controls specified in the health and safety plan.

3. Consultation

If danger exists in the work area due to overhead electrical lines running (a) over

a site, (b) near the site boundaries or (c) over access roads to the site, it is

essential that the Contractor or person undertaking the work should consult

with ESB Networks. This consultation should take place at the planning stage

so that the proposed work can be discussed in relation to any overhead

electrical line that may exist on or near the proposed site. Such an approach will

provide an adequate time span where the line can be switched out and earthed,

but typically for only part of the day, or otherwise, i.e. that the line can be

diverted or that other precautions, as described below, can be taken.

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4. Switchout of Overhead lines

If supply conditions permit the switching out of an overhead electrical line it

becomes a matter of arrangement between the Contractor and the local ESB

Networks Office. Ample advance warning concerning any requirement of this

nature is essential to allow time for changes to be made in existing feeding

methods; for informing customers whose supply or quality of supply would be

affected by the switch-out, etc.

In many instances, such outages can be granted only for a short period, e.g. 2

to 3 hours, due to loss of supply to customers over the switch-out periods and,

unfortunately, at times this option, is not available at all because of the necessity

to maintain an un-interrupted supply to particular types of customers. In general,

switching out the line is not a practical solution in situations where work in

proximity to overhead lines is on-going over a period of time.

Where the switchout of an overhead line is granted, the contractor shall wait for

confirmation by ESB Networks that the line is switched out and not assume that

it is dead at a pre-arranged time. The contractor shall be contactable at all time

during the switchout in case the ESB Networks need to switch the line back on.

5. Diversion of Overhead Lines

Where diversion of the line is a practical option, contact with ESB Networks

must be made as early as possible, e.g. at the planning stage as suggested

above. Time spans for the diversion of LV/l0kV/20kV lines can ( be up to a few

months due to wayleave serving, work load, etc., and that for higher voltages

lines can be as much as one year due to planning permission submissions,

wayleave serving, workload, etc. In certain circumstances it is impossible to

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design a suitable line diversion due to the lack of an alternative route. In

addition, if the work in proximity to a line is of a particular nature, e.g. not

involving the erection of permanent structures over ground, a line diversion

would not be an appropriate or justifiable means of dealing with the problem.

Generally diversions of high voltage lines are not feasible.

6. Working in Proximity to Overhead lines

Where switching out the line or diverting the line, as discussed under 4. and 5.

above is not practicable, the precautions required to prevent accidents

involving LIVE overhead lines depend on the nature of the work. There are three

broad categories of work on site.

(a) Sites where there will be no work or passage of plant under a live line.

Here barriers are required to prevent close approach.

(b) Sites where plant will pass under a live line. Here, defined passageways

under the line must be made.

(c) Sites where work will be done beneath a live line. Here further

precautions must be taken in addition to the provision of barriers and

passageways.

7. Sites where there will be no work or passage of plantunder a Live Overhead Line (all work outside the ‘atrisk zone’)

On sites where machinery or plant may accidentally come in contact with a live

overhead line the Contractor should erect a barrier on the work side (limit of ‘at

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risk zone’) at a minimum distance from the line. The barrier should run parallel

to the overhead at a minimum distance of 6 metres from the nearest conductor

of a low voltage, 10kV, 20kV and 38kV lines. This distance should be increased

to a minimum of 10 metres for voltage of 110kV, 220kV and 400kV. The

distance should be measured from the outer conductor to the barrier and not

from the centre of the pole or mast. Consult ESB Networks to confirm the

voltage of the line. These distances may be increased depending on the nature,

frequency and duration of the work. The barrier should consist of fixed post

fencing, steel drums painted red and white and filled with rubble, spaced 1.5

metres apart or other means approved by a Health and Safety Authority

Inspector. The barrier should be supplemented by notice boards indicating:

"DANGER LIVE OVERHEAD LINES", which should be spaced at intervals of

not more then 20 metres apart along the route. Where a crane, tipper truck or

other high equipment is operating in the vicinity of a live line then the barrier

should be further supplemented. This can be done with a line of bunting or

other approved means of highlighting the hazard at a minimum height of 3

metres immediately over the barrier, see Figure 1 and Figure 6.

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Figure 1


8. Sites where plant will pass under a live Overhead Line

Where movement of plant is necessary under a live overhead line the

Contractor should erect wooden or other non conducting material goal posts at

the entrance to the passage on each side of the line. The goal posts should be

in line with the protection barrier as detailed in 7 above, and the wooden cross-

bar should be set at a height determined in consultation with ESB Networks.

The passageway should be as narrow as possible and should not exceed 10

metres in width and should be fenced or have steel drums on either side. Two

large warning notice boards indicating "DANGER LIVE OVERHEAD LINES"

should be placed near the goal posts at each entrance to the passage. The goal

posts should be marked in red and white stripes, See Figure 2.

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Figure 2.


9. Sites where work will be done within the ‘at risk zone’of an Overhead Line

In general when work has to be carried out close to (within the ‘at risk zone) of

a live line, ESB Networks insists on the line being switched out for the duration

of such work. In some situations, due to continuity of supply considerations, ESB

Networks may be forced to permit work underneath a live line, but only after

detailed consultation with them and with the understanding that strict safety

precautions will be employed. In addition to the precautions outlined in 7 and 8,

it will be necessary for the Contractor to erect a safety barrier underneath the

line. This barrier may be made of timber or an earthed steel net and placed at a

height determined by ESB Networks. It must be erected under the supervision

of ESB Networks so as to avoid danger of contact with the overhead line.

Generally, mobile and fixed cranes should be located in such a position that

loads cannot be slewn over live lines. If there is a need to slew over power lines,

always contact ESB Networks in advance to ensure that agreed precautions

are put in place before the slewing operation.

10. Maintenance of barriers and warning notices

In all cases covered under 7 and 8 and 9 above, a care and maintenance

system must be introduced by the Contractor in order to ensure that barriers

and warning notices remain effective for the duration of the work.

11. Special Precautions

• Always remember that, in common with electrical utilities worldwide,

ESB Network's overhead electrical lines are bare conductors. In the rare

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situations where one finds covered conductors this covering is largely for

mechanical protection of the overhead line and is not a fully rated

insulation and must be treated with the same precautions as bare

conductor.

• ESB Networks must be contacted whenever it is proposed to work in the

vicinity of their overhead electrical lines.

• Contact with or coming close to overhead electrical lines can be lethal

whether they are carrying voltages as high as 400,000 volts or as low as

220 volts. High voltages in particular can arc across a distance in air, and

this makes it hazardous to come close to high voltage lines ranging from

10kV to 400kV.

• Clearance from overhead electrical lines should not be reduced by the

dumping or tipping of waste material, by landscaping operations or by

the creation of storage areas under these lines.

• Pre-planning of safe working procedures is essential.

• Liaison with ESB Networks should be continued until the construction

work has been completed.

• Access for plant and materials and the working of plant should be under

direct supervision of a responsible person appointed by the Contractor

to ensure that the safety precautions are observed.

• Self-adhesive danger stickers (obtainable free from ESB Networks) that

warn machinery operators of the hazards of working in close proximity to

overhead electrical lines should be placed on the cab window, doors or

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dash of machines and vehicles.

• Before starting work in the vicinity of overhead electrical lines, machinery

operators in particular, should be briefed by their responsible supervisors

on the dangers existing and the precautions to be observed.

• In the absence of specific information provided by ESB Networks, it

must be assumed at all times that an overhead electrical line is live.

• Should a vehicle accidentally come in contact with an overhead line, stay

in the cab if the vehicle is not on fire. If there is a danger of fire, you

should jump clear, stay clear and keep everyone else clear until ESB

Networks arrive. On no account should you return to the vehicle.

• It is your responsibility to enure that any machinery or equipment (eg.

ladders, cranes, scaffolding etc.) set up outside the ‘at risk zone’ (see

section 7) is stable and that precautions are put in place to prevent them

from falling into the ‘at risk zone’.

12. Communicating the Safety Message

• ESB Networks advertise regularly on television and newspapers on the

dangers of working near overhead lines in an effort to ensure that

contractors and high machinery operators are fully aware of the hazards.

• In addition to this booklet, a safety poster giving brief details and

illustrations of the precautions required when working near overhead

lines is available from ESB Networks. The poster is entitled

“AVOIDANCE OF ELECTRICAL HAZARDS WHEN WORKING NEAR

OVERHEAD ELECTRIC LINES”

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Figure 3.

• In addition to the above, Goal Posts should be erected as shown

Dimensions as follows:Height of goalposts

- As advised by ESB

Width of Goalposts - Max. 10 metres.

Height of bunting - 3 metres

Distance between steel drums- 1.5 metres

Distance between danger notices- 20 metres

Horizontal distance of barrier to outside conductor on line - 6 metres minimum for LV, 10kV, 20kV, 38kV.- 10 metres minimum for 110kV, 220kV, 400kV.

At the planning stage and before startingwork near an overhead line consult your

local ESB office.THERE ARE TWO GENERAL CASES

• A barrier should run parallel tothe line. (See below for distance from line)

• This may be fixed post fencingor steel drums filled with rubble spaced 1.5 metres apart.

• If cranes are in use a line ofbunting at a height of 3metres should supplement thebarriers. (See below for distance from line)

• Danger notice stating “DangerLive Overhead Line” should bespaced at intervals.

SITE WHERE PLANT WILL PASS UNDER A LIVE OVERHEAD LINE

AVOIDANCE OF ELECTRICALHAZARDS WHEN WORKING

NEAR OVERHEAD LINES

SITE WHERE THERE WILL BE NO WORK OR PASSAGE OFPLANT UNDER A LIVE OVERHEAD LINE

In general if work is to be undertaken directly under the line, ESB will insist that the line is switched off for the duration of the work.

ESB may permit working under a live line only if special agreed precautions are put in place.Booklet (ESB Code 9803203) also available which gives greater detail.


• Cab stickers, For Tipper Trucks, Cranes, Diggers and Tractors are also

available from ESB Networks. These should be stuck on a prominent

place on the vehicle and are a reminder to the Driver/Operator of the

hazards associated with the machine coming in contact with overhead

lines. All cab stickers contain the following safety message: “IF YOUR

MACHINE CONTACTS AN ESB Networks LINE, JUMP CLEAR AND

KEEP OTHERS CLEAR”

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ESB Code 9803052 ESB Code 9803128

Figure 4.

98066359806636 9806634

9806637 98066329806633


• Two videos are also available which

cover the hazards associated with

electricity. These are entitled

“Lifelines” and “Power2Shock”. The

“Lifelines” video recreates 6

accidents caused by machinery

coming in contact with overhead

lines and underground cables. The

6 accident scenarios depicted are

based on real situations where

people have lost their lives in the

past and involve the following:

Tipper Truck, Mobile Crane,

Wheeled Digger, Painters

Scaffolding, Cement Truck and

Tractor coming in contact with

overhead lines or underground

cables. The “Power2Shock“ video

cover the following 4 accident

scenarios: Mini Pillar Vandalism,

Tree Cutting, Elevated Platform and

Mini Digger

All of the above are available from ESB

Networks free of charge to interested

parties.

Bunting and danger signs can usually be

sourced locally from danger sign

manufacturers.

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LifelinesLifelinesAvoiding Accidents

from Overhead Lines &

UndergroundCables

Figure 5.

ESB Code 9803503

ESB Code 9803509


Example of Rigid Goalposts and Barriers

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Goalposts(rigid, not conductive)

Figure 6.

DimensionsA - height to be specified by electricity supplierB - width to e determined by site conditions (max 10m)C - height 3-6mD - 6m (maximum)E - 6m (minimum)

‘At Risk Zone’

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ESB Networks EMERGENCY CONTACT NUMBER1850-372 999

071-914 9349

091-741923

061-430552

021-484 4313

058-42449

Head Office01-702 6119

046-9066770

FOR TECHNICAL INFORMATION AND SUPPORTCONTACT ANY OF THE FOLLOWING NUMBERS

IN YOUR LOCATION

Dublin CentralSouth and North

01-604 2807


Acknowledgement of Receipt of

Avoidance of Electrical Hazards

when Working Near Overhead Electric Lines

I have received on the date under my signature ______ copies of the above

booklet..

Please detach this page and return to the ESB Networks member of staff who

supplied the booklet(s)

Only necessary to return one signed sheet, irrespective of the number of

booklets received.

You may wish to keep local records in a similar manner, for the booklets which

you issue onwards to your staff or contractors

Signed: _______________________________________________

Date: _______________________________________________

Company Name: _______________________________________________

Address: _______________________________________________

_______________________________________________

_______________________________________________

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• Check for the presence of underground cables when planning any dig orexcavation. Contact ESB Networks at 1850 372 757 for details.

• Make sure that your staff and sub-contractors are made aware of the presence ofany cables and that they observe safe digging and excavating practices.

• Remember, contact or even slight damage or movement can cause a cable to explode.

Take particular care with:✓ Excavators

✓ Mini-diggers

✓ Rock hammers

✓ Concrete saws

✓ Hand digging

Supporting Safety in the Construction Industry.

Beware of buried cables

ELECTRICITY IS A GREAT FORCE OF NATURE. RESPECT ITS POWER.


Overhead lines electrical_hazards

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